Subject: Is State-based LDUP needed?

From: "Ed Reed" <[email-masked]>
Date: Thu, 13 Dec 2001 21:05:25 -0700

I asked this question at the ldup meeting on Thursday, and agreed to post the question to the distribution list.

Is anyone planning to implement state-based ldup?  If not - that is, if there are not going to be at least two interoperable implementations of the proposed specification, should we not remove it from the ldup design now, rather than later?

The protocol will support it, but there are certainly places in the architecture and other documents where the different handling of change information required by the state-based scheme adds unnecessary text if noone is actually going to use it.

This is a pragmatic decision - I personally like state based schemes, even though there are things (like transaction replication) that I doubt they'll ever be able to handle well.  Also, all the implementers I know are focused on the log-based scheme, instead.  It seems easier for them to get their heads around, for some reason...

So - I don't think it's appropriate for me to be the only one championing it, and have reached the conclusion that if we can't find even two implementers to build it, we should not bother including it in further work.

If you're planning to build it, speak up.  If not, silence may well be taken as assent to remove references to it from the various protocol documents.

Best regards,
Ed

Ps - yeah, I know, you told me so...

=================
Ed Reed
Reed-Matthews, Inc.
+1 585 624 2402
http://www.Reed-Matthews.COM
Note:  Area code is 585

---

From: "Timothy Hahn" <[email-masked]>
Date: Fri, 14 Dec 2001 07:27:02 -0500

Ed,

First, I'll say that we've only been looking at log-based implementations 
- probably because we see benefits in doing this way.

Second, it occurs to me that LDUP really doesn't need to have two 
interoperable "state-based" implementations - it just needs to have two 
interoperable implementations (regardless of state-based/log-based). Thus, 
I don't quite follow your argument that we'd need at least two state-based 
implementations to leave "state-based" references in the specs.  If/when 
we get two interoperable implementations (state-based or log-based), that 
would be enough I would think.

Either way though, if just concentrating on "log-based" moves the specs 
along quicker, I'm all for it.

Regards,
Tim Hahn

Internet: [email-masked]
Internal: Timothy Hahn/Endicott/IBM@IBMUS or IBMUSM00(HAHNT)
phone: 607.752.6388     tie-line: 8/852.6388
fax: 607.752.3681

"Ed Reed" <[email-masked]>
Sent by: [email-masked]
12/13/2001 11:05 PM

        To:     <[email-masked]>
        cc: 
        Subject:        Is State-based LDUP needed?

I asked this question at the ldup meeting on Thursday, and agreed to post 
the question to the distribution list.

Is anyone planning to implement state-based ldup?  If not - that is, if 
there are not going to be at least two interoperable implementations of 
the proposed specification, should we not remove it from the ldup design 
now, rather than later?

The protocol will support it, but there are certainly places in the 
architecture and other documents where the different handling of change 
information required by the state-based scheme adds unnecessary text if 
noone is actually going to use it.

This is a pragmatic decision - I personally like state based schemes, even 
though there are things (like transaction replication) that I doubt 
they'll ever be able to handle well.  Also, all the implementers I know 
are focused on the log-based scheme, instead.  It seems easier for them to 
get their heads around, for some reason...

So - I don't think it's appropriate for me to be the only one championing 
it, and have reached the conclusion that if we can't find even two 
implementers to build it, we should not bother including it in further 
work.

If you're planning to build it, speak up.  If not, silence may well be 
taken as assent to remove references to it from the various protocol 
documents.

Best regards,
Ed

=================
Ed Reed
Reed-Matthews, Inc.
+1 585 624 2402

---

From: "Ed Reed" <[email-masked]>
Date: Mon, 17 Dec 2001 17:53:36 -0700

Tim -

I guess I'd consider it a failure if only one state-based system were developed under the spec.  If there were only one, I'd argue that part of the spec should be dropped before being sent forward in the standization effort.

At this point, I don't even know of one committed vendor to the state-based version.

Ed

>>> "Timothy Hahn" <[email-masked]> 12/14/01 07:27AM >>>
Ed,

Regards,
Tim Hahn

        To:     <[email-masked]>
        cc: 

Best regards,
Ed

=================
Ed Reed
Reed-Matthews, Inc.
+1 585 624 2402